At the same time, much innovation is expected to occur in the area of specialty drugs –– drugs to treat such complex and often unmet therapeutic needs as multiple sclerosis, cancer and hepatitis C –– and patient access is expected to increase. IMS predicted five potential blockbuster drugs, meaning those with annual sales of $1 billion or more, will be approved over the course of the year.

Public and private payers are expected to reduce their growth in drug budgets, according to the report. In the United States, this is in the form of health plans increasing use of cost-sharing provisions and pre-authorizations.

“In 2011, we will see the loss of exclusivity for some iconic brands and a promising new wave of innovation,” IMS SVP Murray Aitken said. “It will also be a critical year for gauging how healthcare-reform initiatives in key markets evolve and play out amid the expected macroeconomic recovery. For pharmaceutical manufacturers, an unrelenting focus on bringing distinct value to patients and health systems will be essential to navigating this dynamic market.”

Overall, the company expected divergent growth in different markets. The United States will remain the largest drug market, growing 3% to 5% to $310 billion. Japan will grow by 5% to 7%, while Canada and the five major European markets of the United Kingdom, Germany, Spain, Italy and France will grow by 1% to 3%. The so-called “pharmerging markets” will experience the most dramatic growth, 15% to 17%, including 25% to 27% growth in China, which will remain the world’s third-largest pharmaceutical market at $50 billion.